Vanxa



1'. v I it Jill ll is: is

GHARLES L. noose .unecirnio timiurmo'romue COMPANY, 12, oozeieonowxon oi" Pmmsnn involution, ZBETTSBURGH, rhuus'ytvenin, ASSIGNOR T0 wesi me- ,Plttfi fili lilfi.

lilo Knowing. .ilpplicetion 1 all whom it may cone em known thatl. Gimmes ll. Summon,

2 Flint )urgh, in the county of llllleghei'iy :lnli Stww of Pennsylvania, he vented eoi'toin new and isei ul IHULJW} o nte in the Munufaeture of Treated Stone, of which the tollowing is a specification.

My invention, relates to the precinct/ion of u material adapted for use a. substitute for the marble shite. 111d similar materials heretofore used. in making the non-conlucting hocking for switch-hoards, tablet hoards, switc-h hoses; insulators, and, similei electrical apparatus. and as stair treads uncl simii211 mtioles requiring superior weorimg qualities. I

(l ne object of the invention is tof'treet natural stones such as Euclid blue stone 01' llerea. grit, oolitic liinestones, and similox; natural stones-z founcl in large quantities in vei'ious ports of the United States, so as to make the ti'eatecl materiel iinpeivious to moistuire and to imp-eitto it high electrical resistance qualities mum greater than are found in. shite end cquol to the best nm1'ble, the materials universally used. for such. pur poses up to the present tiine.

Another object oi the invention is to treat A still further object of the invention is the ptoduction of the new article o't mztn11-- lecture obtained iuczu-gcyiuwout my novel method and forming the subject matter of part of the appended claim.

In carrying out my hnorovecl method a natural stone having the characteristics as to structure and composition of the semistones known as l lucliil blue stone or BQI'QZTL grit, or oolitir liniestoues, is first out to the December 153115;

(lQSlYHl outline and dimensions.

of the United States, end resident to treat;

between, 170 and 212 degrees Fahrenheit.

hex-ml Ef-lo. Home.

The out inetei iol is then grzuluelly heated in a suitable furnace, or in other approved manner, to it teinoer'iture of from 212 to 6W0 degrees l 'oln'enheit .1

within such range of temperature for a. time interval of from 2 to 6 hours so as to thereby (lrive ofi all moisture from the heated materiel.

material being mointoinetl When it is to be colored the material is then allowed to cool until at or slightly below e temperature of 250 (legiees Fahrenheit and. is then immersed in a. heated solution.

of on onilin coloring material. Nigrosin, a.

black zinilin. coloring material has been found to he a desirable coloring material when a black color is to he imported to the material.

The material is allowed to remain in the coloring solutioi'l which is maintained at o,

temperature'ol" about 212 degrees Fahrenheit, for suihcienttime to ceuse the stone to absorb and become impregnated with the solution. lifter being removed. from the solution the material is placed in 3, suitable furnace or oven, or is heated in any other clesired mennei', to such. temperature and for such time interval necessary to drive oil the liolvent enrl thoroughly dry the meteriel.

When dried the material is then immersed in a. bath of melted pemilin WhlOh lS heated above the melting pointof. paraffin. (about l33degrees Fehienheitlancl preferably to His desirable to not exceed 212 degrees Fahrenheit.

The material is kept in the loath of poi'afiin for sufficient time to cause the pemffin to penetrate throughout the porous stone or. other materiel being treated, so that the sotreetefcl stone will absorb paraffin until sat hinted therewith. Experiments have shown that ,3. material such as Euclid jolue stone having a thickness of oneinoh will become thoroughly saturated: after from five to eight hours immersion in the heated pom-fin,

When-the pemffin is maintained at a. temper attire 6i epproxiinetely 170 degrees 'Foln'en},

lieit;'-". In sogne oo'see, however, it will be necessary tomeintoin, the material in the otion bath-for from 24 to48 hours. In all cases the porosity of the material and the temperature of the paraiiin hath as Well as the thickness of the material being treated,

will be taken into consideration, the object being to cause the paraffin to penetrate throughout orsaturate' the material being treated. The amount of paraffin Which is absorbed by the material is comparatively small, ordinarily being about 3 per cent. of the Weight of the material treated.

After the material is removed from the pereifin bath it is permitted to cool a dry atmosphere and the so-treated material. will he found to he in readiness for. the use to which it is to he put. f

Tests show that the electrical resistance of the treated material forming my improved product'will have been very materially increased, in some cases being tripled and in most cases being equal to marble, the material heretofore universally used in making switch-board beckings and similar electrical apparatus used in high tension Work.

Modifications in the composition of the solution of coloring material used and changes in the steps comprising my im- 25 proved method may be made. T he material may be treated before being out to dimensions. The color imparted to the materials may be changed. A vacuum systenimay be employed in drying the materials and in impregnating the same, and other variations may be made; without departing from my invention as defined in the appended claim.

I claim? v i That Way of treating natural stone which 35 comprises immersing the stone in a heated solution of enilin dye to thereby impregnate the stone with coloring material, heating the anilin'impregnated stone until freed y of the solvent of the dye, and then immersing} the dried stone in molten parafi'ih until saturated l'zherewith the molten paraffin being maintained at. temperature of 170 to 219 degrees Fahrenheit.

in testimony whereof I have hereunto set, my hand.

CHAR-LES L. 

